1. Field of the Invention
The present invention relates to a vehicle front structure including a large-size upper dashboard which frontward extends from an upper end portion of a lower dashboard separating an engine compartment and a vehicle compartment.
2. Description of the Related Art
JP2006-213291A (paragraphs 0024-0025, FIGS. 1 and 3) discloses a vehicle front structure including an upper dashboard separating an engine compartment and a vehicle compartment, and right and left damper housings for holding corresponding right and left dampers. In such a vehicle front structure, the upper dashboard is connected to the right and left damper housings at corresponding end portions of the upper dashboard, and drain grooves are formed in a front portion and a rear portion of the upper dashboard, each extending in a longitudinal direction of the upper dashboard (vehicle width direction) and having a U-shaped cross section in a front-rear direction. With this structure, strength of the upper dashboard is enhanced, which in turn enhances strength of the right and left damper housings.
Along with the recent improvements in performances of automobiles, the number of devices to be mounted in the engine compartment has been increasing. For example, it is demanded that brake-parts or the like be mounted in the vicinity of the damper housing. Especially in a hybrid car, in addition to the conventional engine, many electrical equipment parts or the like associated with a motor are expected to be held in the engine compartment. Therefore, it has been highly demanded to utilize a space under the upper dashboard.
Further, in order to improve body rigidity of the vehicle, especially rigidity around the damper housing, proposals have been made in which a stiffener is fixedly installed to an upper face of the upper dashboard, in such a manner that the stiffener connects the right and left damper housings.
However, in the vehicle front structure described in the above-mentioned patent document, the end portions of the upper dashboard are joined to the respective damper housings, leading to poor utilization of a space under the upper dashboard, such as for mounting brake-parts or the like.
In addition, since the strength of the upper dashboard is not satisfactory, it has been conventionally avoided to suspend vehicle parts from the upper dashboard. In the upper dashboard described in the above-mentioned patent document, rigidity (section modulus) is reinforced with the formation of the drain groove having a U-shaped cross section. Even so, a weight that can be suspended from the upper dashboard is still small, and rigidity reinforcement of the upper dashboard has been further desired.
In the case of a large sized upper dashboard, low-frequency noise (also referred to as drumming noise) may be generated due to resonance with vehicle vibration, and suppression thereof is demanded.
Furthermore, when the stiffener is fixedly installed to the upper face of the upper dashboard so as to connect the right and left damper housings, at least three steal plates (four steal plates when a damper flange is included) should be welded in a overlapped state on an upper face of the damper housing, making it difficult to perform secure welding. As a result, load cannot be efficiently transferred from the damper housing to the stiffener, and the damper housing may not be efficiently reinforced.
Therefore, it would be desirable to provide a vehicle front structure in which rigidity from the upper dashboard and the damper housing is surely improved, and thus noise is surely reduced, and at the same time, a space under the upper dashboard is efficiently used for mounting parts (for example, a structure that makes it possible to fixedly suspend the parts and to allow access for maintenance).